Somewhere Jack Webb is smiling. The hard-ass actor who played dirty-hippie–hating Det. Sgt. Joe Friday on 1960s police procedural “Dragnet” proselytized about the dangers of pot, grass, Mary Jane, reefers — whatever you want to call it. Now, as America is in the midst of a spree to legalize marijuana (for both medical and recreational uses), researchers in Philadelphia have dumped cold water on the pot party.

A new study by the American College of Cardiology says that using marijuana raises risks of stroke and heart failure by 26 percent and 10 percent, respectively — and that was after researchers adjusted for other risk factors such as obesity, high blood pressure, smoking and alcohol consumption.

In other words, there are more serious reasons to not pass the dutchie besides the munchies and occasional bouts of paranoia.

“Even when we corrected for known risk factors, we still found a higher rate of both stroke and heart failure in these [marijuana consuming] patients, so that leads us to believe that there is something else going on besides just obesity or diet-related cardiovascular side effects,” said Dr. Aditi Kalla, a cardiology fellow at Philadelphia’s Einstein Medical Center and the study’s lead author, in a press release. “More research will be needed to understand the pathophysiology behind this effect.”

The findings, which will be presented at the ACC’s annual Scientific Session that starts Friday, lends credibility to some of the more reactionary opinions from opponents to the legalization of marijuana.